Texas, USA – A thermal power station required a high-wearing, low maintenance bearing alternative for a condensate pump assembly. The line shaft and pump bowl bearings used in this vertical spindle pump operate in pure water conditions at a temperature ranging between 30˚C and 60˚C (86°F to 140°F). Removal and maintenance cost on the pump are high. Vesconite Hilube bearings were manufactured and fitted. Resultant performance has been impressive – the replacement bearings have run without fault for four years, on a pump assembly that has a seven yearly maintenance rebuild schedule.
Water Utility Uses Hilube on Vertical Spindle Pumps
Texas, USA – A water utility in Texas had over the years experimented with different grades of nylon bearings in its vertical spindle pumps, but with little success. The pumps operated in the abrasive conditions found in pit-wells. The combination of debris and sand would eventually lead to excessive wear of the original bushings and eventual seizure. The original parts were subsequently replaced with Vesconite Hilube, which requires no lubrication, does not swell and can operate in dirty conditions as characterized by the above. The re-fitted pumps have since been running without incident for over a year now.
Why Use Vesconite in Pumps?
Vesconite has been used for decades in a wide range of specialized pump bushing applications. The material thrives in water and exhibits excellent dimensional stability, with zero delamination. The result is low downtime and associated hassle factor. Its friction coefficient range of 0.1 – 0.2 allows for dry starting – an issue commonly associated with high wear rates in traditional bushing materials. Corrosion of the bushing is entirely eliminated with Vesconite, Vesconite Hilube is recommended for most pump applications.
Benefits for Pumps
- Vesconite does not swell or distort in water.
- Vesconite does not delaminate.
- Vesconite does not corrode.
- Vesconite requires no lubrication.
- Vesconite is resistant to oils and fuels.
- Vesconite bushings are easy to fit and remove.
- Vesconite prolongs shaft life.
Common Pump Applications
- Lineshaft bushings in vertical turbine pumps.
- Support bushings and wear rings in pumps.
- Stuffing box bushings in vertical turbine pumps.
- Impeller support bushings in sump pumps.
In the case of pump impeller and case wear rings, tight clearances are required. Swelling and distortion can be an issue with traditional bushing materials. This is not the case with Vesconite due to its virtually zero water absorption rate and dimensional stability.
Unlike bronze or rubber bushings, fresh and saltwater serves as an effective lubricant for Vesconite. This makes it an ideal material for pump bowl bushings and stuffing box bushings.